67 427/390 fan clutch

[Keith B.]

does this look like the correct one that would have left the the car in St. Louis?



I can still read the ink stamp of "CK" on it.

if this is the correct one does any one know if they will be any one coming to Corvettes at Carlisle in two weeks who restores them?

thanks

[David L.]

Re: 67 427/390 fan clutch

According to my research the "CK" fan-clutch is GM # 3916141 and was used on 68-69 Corvette (427) models. The measurement from the fan mounting surface to the water pump mounting surface should be 1.5". There also should be a date code stamped on the edge of the hub since your fan-clutch was made by Schwitzer.

I believe that the correct fan-clutch for 66-67 Corvette (427) models is GM # 3857531, stamped "CT". GM # 3857531 was replaced with GM # 3916141 in Sept. 1981.

Dave

[John H.]

Re: 67 427/390 fan clutch

does this look like the correct one that would have left the the car in St. Louis?
I can still read the ink stamp of "CK" on it.

Keith -

I don't think that's a Schwitzer fan clutch - doesn't look like any one I've ever seen; appears to be an aftermarket (Hayden?) "Thermatic" replacement. The correct midyear "CK" Schwitzer fan clutch is shown in the photo below.


SchwitzerFanClutch800.jpg

[Keith B.]

Re: 67 427/390 fan clutch

on the hub it is stamped H3074SC so how do you break that down

also on the face it says Patented-Patented Canada 1961 other patents pending thermatic fan drive. in the metal band in the middle it something ink stamped but its a little rusted to read

[Ara G.]

Re: 67 427/390 fan clutch

Keith
That's not what you are looking for. John's pics are what you should be looking for (if a Schwitzer is what you want). Otherwise, there are tons of pics in the Archives of original Eatons...ARA

[David L.]

Re: 67 427/390 fan clutch

on the hub it is stamped H3074SC so how do you break that down

also on the face it says Patented-Patented Canada 1961 other patents pending thermatic fan drive. in the metal band in the middle it something ink stamped but its a little rusted to read

Keith,

"H3074" = August 30, 1974
"SC" = Schwitzer

The 1960's Schwitzer fan-clutches did not use a letter in the date code.

It's definitely a Schwitzer fan-clutch as indicated by the "SC". The Schwitzer company changed the style a bit in the 1970's. Schwitzer was the only company that used the "bar strip". The Eaton and Delco fan-clutches have a coil spring on the front face. I have had dozens of factory installed fan-clutches over the last 30 years.

Does your fan-clutch have 4 holes or 4 open slots for mounting on to the water pump hub?

Dave

[David L.]

Re: 67 427/390 fan clutch

I don't think that's a Schwitzer fan clutch - doesn't look like any one I've ever seen;

John,

It is a Schwitzer fan-clutch (Aug. 30, 1974 stamped "SC"). You just haven't looked long enough.


Dave

[Keith B.]

Re: 67 427/390 fan clutch

it has four holes on the hub. does this fan clutch have any value. it appears to be in working order. thanks for your help

[John H.]

Re: 67 427/390 fan clutch

John,

It is a Schwitzer fan-clutch (Aug. 30, 1974 stamped "SC"). You just haven't looked long enough.


Dave

Dave -

Never looked at the 70's - I'm mired in the 60's.

[David L.]

Re: 67 427/390 fan clutch

Keith,

Based on my research the "CK" fan-clutch (GM # 3916141) was only installed on 1968-1969 Corvette (427) models. I believe that your fan-clutch dated Aug. 30, 1974, was sold over the counter. My 1972 Corvette Parts Catalog lists GM # 3937771 for the 1970 and GM # 3991426 for the 1971-1972 models. I have had a few Schwitzer fan-clutches similar to yours with 1973 & 1974 dates that I sold several years ago for about $25 or $30. You do not have a gold nugget.

Dave

[Richard L.]

Re: 67 427/390 fan clutch

does this look like the correct one that would have left the the car in St. Louis?



I can still read the ink stamp of "CK" on it.

if this is the correct one does any one know if they will be any one coming to Corvettes at Carlisle in two weeks who restores them?

thanks

Keith...

Get in touch with NCRS Member Richard Jones (44319) in Albuquerque, NM...You can contact him though the NCRS Member Services Contact List or shoot me a message and I'll give you his contact info... Does Excellent Work on restoring fan clutches that meets NCRS Judging muster and they actually work as originally designed too... Turnaround time is short...Not sure if he goes to Carlisle or not...

Best of all, He's a Good Person to boot...

Hope this Helps...

Rick